Tax code displays “Not Taxable” import in Sales Order Csv

Scenario: We imported Sales Order Via CSV import, Tax column shows that transaction was Not Taxable even through there were no issues in during the import.

1. In the Global Search, type the customer’s name or number of the customer record.
2. Click Edit Button.
3. Go to the Address Tab.
4. Make sure that the Customer record has a Default Shipping Address.
5. If the customer has several addresses, choose one of them to be the Default Shipping.
6. Click Save Button.
7. Proceed with importing another Sales Order for the affected Customer .